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The Tasman Bridge disaster occurred on the
evening of 5 January 1975, in Hobart, the capital city of Australia's island state of Tasmania, when a bulk ore
carrier travelling up the Derwent River collided with
several pylons of the Tasman Bridge, causing a large section of
the bridge deck to collapse onto the ship and into the river below.
Twelve people were killed, including seven crew on board the ship,
and the five occupants of four cars which fell 45 m (150 feet)
after driving off the bridge. The disaster severed the main link
between Hobart and its eastern suburbs, and is notable for the
social impacts that resulted from the loss of such an important
road artery.

Collision
and collapse

Model showing the scene on the bottom of the Derwent River

The collision occurred at 9:27 pm (Australian Eastern Standard
Time) on Sunday January 5, 1975. The bulk carrier Lake
Illawarra, carrying 10,000 tonnes of zinc ore concentrate,
was heading up the Derwent River to offload its cargo to the
Electrolytic Zinc Company at Risdon, upstream from Hobart and about
3 km from the bridge. The 1 025m long main viaduct of the bridge
comprised a central main navigation span, two flanking secondary
navigation spans, and 19 approach spans. The ship was off course as
it neared the bridge, partly due to the strong tidal current but
also because of inattention by the ship's master, Captain Boleslaw
Pelc.[1]
Initially approaching the bridge at eight knots, Pelc slowed the
ship to a 'safe' speed. Although the Lake Illawarra was
capable of passing through the bridge's central navigation span,
the captain attempted to pass through one of the eastern spans.

Despite several changes of course, the ship proved unmanageable
due to its insufficient speed relative to the current. In
desperation the captain ordered 'full speed astern', at which point
all control was lost. The vessel drifted towards the bridge midway
between the central navigation span and the eastern shore, crashing
into the pile capping of piers 18 and 19, bringing three
unsupported spans and a 127 m section of roadway crashing into the
river and onto the vessel's deck. The ship listed to starboard and
sank within minutes in 35 m of water a short distance to the south.
Seven crew members on the Lake Illawarra were trapped and
drowned. The subsequent maritime inquiry found that the captain had
not handled the ship in a proper and seamanlike manner, and his
certificate was suspended for 6 months.[2]

As the collision occurred on a Sunday evening, there was
relatively little traffic on the bridge. While no cars were
travelling between the 18th and 19th pylons
when that section collapsed, four cars drove over the gap, killing
five occupants. Two drivers managed to stop their vehicles at the
edge, but not before their front wheels had dropped over the lip of
the bridge deck. One of these cars contained Frank and Sylvia
Manley, travelling with two young children in the back seat.

Sylvia Manley: "As we approached, it was a foggy
night...there was no lights on the bridge at the time. We just
thought there was an accident. We slowed down to about 40 km/h and
I'm peering out the window, desperately looking to see the
car...what was happening on the bridge. We couldn't see anything
but we kept on travelling. The next thing, I said to Frank, "The
bridge is gone!" And he just applied the brakes and we just sat
there swinging.[3]As we sat there, we couldn’t see anything in the water. All we
could see was a big whirlpool of water and apparently the boat was
sinking. So with that, we undid the car door and I hopped
out." [4]

Frank Manley: "[Sylvia] said “The white line, the white
line’s gone. Stop!" I just hit the brakes and I said “I can’t, I
can’t, I can’t stop.” And next thing we just hung off the
gap...when I swung the door open, I could see, more or less, see
the water...and I just swung meself towards the back of the car and
grabbed the headrest like that to pull myself around. [4]
There's a big automatic transmission pan underneath [the car] -
that's what it balanced on." [3]

Emergency
response

Private citizens living nearby were on the scene early, even
before the ship had sunk. Three of these were Jack Read in his H28
yacht "Mermerus", David Read in a small launch, and Jerry
Chamberlain, who had their boats moored in Montagu Bay close by.
These and others, and many shore based residents were responsible
for saving many of the crewmen from the Lake Illawarra. Those in
small craft acted alone in very difficult circumstances with
falling hunks of cement, live wires, and a torrent of water from a
broken water main above, until the water police arrived on the
scene. A large number of other organisations were involved in the
emergency response, including police, ambulance service, fire
brigade, Royal Hobart Hospital, Civil
Defence, the Hobart Tug Company, Marine Board of Hobart, Public
Works Department, Transport Commission, HydroElectric Commission,
Hobart Regional Water Board, the Australian Army and the Royal
Australian Navy. At 2:30 am, a 14-man Navy Clearance Diving Team
flew to Hobart to assist Water Police in the recovery of the
vehicles which had driven off the bridge. Two vehicles were
identified on 7 January; one salvaged that day and the second three
days later. Another vehicle was found buried under rubble on 8
January.

A comprehensive survey of the wreck of the Lake Illawarra was
completed by 13 January. The divers operated in hazardous
conditions, with minimal visibility and strong river currents,
contending with bridge debris such as shattered concrete,
reinforced steel rods, railings, pipes, lights, wire and power
cables. Strong winds on the third day brought down debris from the
bridge above, including power cables, endangering the divers
working below.[5]

A divided
city

Geography of Hobart, showing the main part of the city on the west
(green), and outer suburbs (blue)

View of the Derwent River dividing Hobart

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Facilities

The collapse of Tasman Bridge isolated two sides of the city
which had heavily relied upon it for most daily activities.[6] 30% of
Hobart's residents lived on the eastern shore and were effectively
isolated. The day after the incident, as some 30,000 residents set
out for work, they found that the former three-minute commute over
the bridge had turned into a ninety-minute trip.[7]
Within an hour of the incident, the Sullivans Cove Ferry
Company started services between both shores of the river, and
continued their services throughout the night.

Three private ferries and a government vessel were in place the
next day. People on the Eastern Shore quickly became isolated, as
most schools, hospitals, businesses and government offices were
located on the Western Shore. Prior to the disaster, many services
on the eastern shore were severely lacking.[8]
Access to medical services in particular, posed problems for
residents in the east, as services consisted only of local clinics.
Hobart's hospitals—the Royal Hobart Hospital and the Calvary Hospital—were located
on the Western Shore. What was previously a short drive across the
river became a 50 km (31 mile) trip via the estuary's other bridge
in Bridgewater. Most of Hobart's
cultural activities, such as theatres, cinemas, the museum and art
gallery, restaurants, meeting places, lecture theatres and the
botanical gardens, were located on the western shore.[9]

Social
effects

The disaster caused a variety of social and psychological
difficulties. Although comparatively minor in loss of life and
damage, it presented a problem beyond the capacity of the community
to resolve.[7]
The disaster had a number of unique characteristics and occurred at
a time when the effects of disasters on communities were not well
understood. Opportunities for the community to be involved in the
response to the disaster and the physical restoration of
infrastructure were minimal because of the nature of the event. It
is likely that this lack of contribution contributed to the
enduring nature of the effects of the disaster on a number of
individuals.[9]

A study of police data found that in the six months after the
disaster, crime rose 41% on the eastern shore, while the rate on
the city's western side fell. Car theft rose almost 50% in the
isolated community, and neighborhood quarrels and complaints rose
300%.[7]
Frustration and anger was directed towards the transport services.
Visible progress on restoration of the bridge was slow because of
the need for extensive underwater surveys of debris and the time
required for design of the rebuilding. The ferry queues did however
provide some assistance by providing a forum where people with much
in common could vent their frustration.[9]
A sociological study described how the physical isolation led to
debonding (the setting aside of bonds that constitute the fabric of
normal social life). The loss of the Tasman Bridge in Hobart
disconnected two parts of the city and had far reaching effects on
the people separated.[10]

Rebuilding

Repairing the Tasman
Bridge

View from the eastern shore showing the rebuilt pylons

In March 1975, a Joint Tasman Bridge Restoration Commission was
appointed to restore the Tasman Bridge. The Federal Government
agreed to fund the project, which began in October that year. The
reconstruction included modification of the whole bridge to
accommodate an extra traffic lane, allowing for a peak period
'tidal flow' system of three lanes for major flow and two for the
minor flow. Approximately one year after the bridge collapse, a
temporary two lane bailey bridge 788 m long, linking the
eastern and western shores of the Derwent, was opened. [8]

Specialists in marine engineering undertook an extensive
investigation to locate bridge debris. This survey took a number of
months to complete, and parts of the bridge weighing up to 500 tons
were accurately located using equipment developed by the University
of Tasmania and the Public Works Department. Maunsell and Partners
were appointed consultants for the rebuilding project. The firm
John Holland was awarded the construction contract.[11]Engineers
decided not to replace pier 19 as there was too much debris on the
site.[12] The
Tasman Bridge was re-opened on 8 October 1977, nearly three years
after its collapse.[1]
The annual expenditures on the Tasman Bridge reconstruction were
$1.7 m in 1974–75; $12.3 m in 1975–76; $13.2 m in 1976–77 and $6.1m
in 1977–78.[13]

The engineering design of the Tasman Bridge provided impact
absorbing fendering to the pile caps of the main navigation span
capable of withstanding a glancing collision by a large ship, but
all other piers were unprotected. This disaster shares some common
features with the Skyway Bridge collapse in
Florida in 1980, and the I-40 Bridge Disaster in Oklahoma
in 2002, both involving collisions with ships. When river traffic
"comprises large vessels, even at low speed, the consequences of
pier failure can be catastrophic". In the field of structural
engineering, the concept of ‘pier-redundant’ bridges refers to a
bridge superstructure which does not collapse when a single pier is
removed. [14] Two
‘pier-redundant’ bridges have been constructed in Australia - over
the Murray River at Berri and at Hindmarsh Island in South
Australia. The probability of ship impact is now regularly
evaluated by specialist consultants when designing major bridges.
One solution is to protect bridge piers through strengthening or
the construction of impact-resistant barriers [15]

The disaster resulted in changes to the regulations pertaining
to shipping movements on the Derwent River. The Marine and Safety
(Pilotage and Navigation) Regulations (2007) contains specific
provisions dealing with the Bridge, eg:

"The master of a vessel approaching the Bridge to navigate
it through a span must (a) have the vessel fully under control; and
(b) navigate the vessel with all possible care at the minimum speed
required to pass safely under the bridge".[16]

Vessels above a certain size are required to be piloted, and
vehicle movements on the bridge are temporarily halted when large
vessels are to pass underneath the bridge. As an added precaution,
it is now mandatory for most large vessels to have a tug in
attendance as they transit the bridge in the event that assistance
with steerage may be needed.

Development on the eastern
shore

Recent panorama of Hobart illustrating the extent of the city's
reliance on the Tasman Bridge

The disaster stimulated development in Kingborough, a
municipality south of Hobart on the western shore, because of the
reduced travel times for western shore workers compared to the
eastern shore. The eastern shore eventually became a more
self-contained community, with a higher level of employment and
improved services and amenities, than had been the case prior to
the disaster. The previous imbalance between facilities and
employment opportunities was redressed as a result of the
disaster.[9]

A new bridge crossing the river, the Bowen Bridge, was completed in 1984, a few
kilometres north of the Tasman Bridge.

Memorial

A plaque on the side of the eastern bridge support

A small service, led by members of the Tasmanian Council of
Churches, was held on the occasion of the reopening on Saturday 8
October 1977. A large memorial service was eventually held 25 years
after the disaster, in January 2000. In his address to the
gathering, the Tasmanian Premier Jim Bacon stated that some people were still
struggling with the memories of its effects, and he commended the
resilience of the community in coping with the disaster. The
Governor at the time, Sir Guy Green, described the pain and
loss of loved ones and the social and economic disruption. He paid
tribute to the efforts of emergency services personnel in
responding to the disaster. He said that the "eastern shore had
emerged more self-sufficient in the wake of the tragedy" and that
"Tasmanians were now stronger, more self-reliant and mature".[9]
A plaque commemorating the tragedy was affixed to the main bridge
support on the eastern shoreline.